Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
g

Test String

Code Generator

Language

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`((?:\\033|\e|\\x1B|\\x1b){1}(?:\[(?:=|\?|[0-9]*)[0-9]*[a-gA-GnmsuJKhlHL]{0,1}(?:(?:\;[0-9]*)*m){0,1}))`) var str = `0x7ffff00196a0 "\r\r\r\033[9999B[\033[m\033[36madmin\033[m@\033[m\033[32mLeonards_switch\033[m] > " \r routerboard: yes\r\n model: CRS112-8P-4S\r\n revision: r2\r\n serial-number: F1 4F0FC0637C\r\n firmware-type: qca8513 L \r \n f a c t o r y - f i r m w a r e : 6 . 4 7 . 1 0 \r \n c u r r e n t - f i r m w a r e : 6 . 4 7 . 1 0 \r \n u p g r a d e - f i r m w a r e : 6 . 4 7 . 1 0 \r \x1b[1;31mHello \x1b[2;37;41mWorld \033[38;2;1;22;252m \033[38;5;5m \033[48;5;5m \033[48;2;15;251;3m \033[0J \033[J \033[1J \033[3J \033[K \033[0K \033[u \033[s \033[8 \033[7 \033[m \033[6n \033[5G \033[=14h \033[=15l \033[?25h \033[?1049l` for i, match := range re.FindAllString(str, -1) { fmt.Println(match, "found at index", i) } }

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Golang, please visit: https://golang.org/pkg/regexp/